DESCRIPTION: (adapted from the application): Increasing life expectancy and improving health are hallmarks of the 20th century. World leaders have recognized that these benefits of social and health advances have produced a growing number of elders, leading to opportunities and to new challenges to nations. The final communique of the 1997 G8 Summit emphasized the need for the leading nations to work together, within the OECD, and with other international organizations, to promote active aging through information exchanges and cross-national research. These investigators noted that particularly important research challenges included: (1) reducing disability, (2) understanding how policies and programs might promote or deter active aging, (3) redefining retirement and work, (4) identifying areas in which structural reforms are needed to preserve and strengthen the G8 countries pension, health and long-term care systems. The four themes of the proposed CDEHA reflect these concerns of the leading thinkers of our world. However, each of these theme areas will need additional infrastructure to maximize the opportunities for international comparative research, communication, and training. The External Innovative International Network Core will be developed with the following specific aims: (1) To expand the membership and activities of the current international network to address the challenges of population aging, particularly in instances where the research supports meaningful insights related to the U.S. population and important subgroups (i.e., oldest old, elderly women), and to the effects of U.S. social and health care policies. (2) To improve communication among network participants and disseminate research findings and information to other investigators and the public with Internet-based and other technologies.